This invention relates generally to the dryer art and relates, more particularly, to a desiccant dryer which is connectable within a gas line or the like for absorbing moisture contained in gas flowing through the line.
The type of dryer with which this invention is to be compared commonly includes two cylindrical containers, or towers, each filled with desiccant supported therein in a packed bed arrangement and adapted to accommodate a flow of gas from one container end to the other. Such towers are typically connected in parallel flow relation with one another in a gas line so that the gas flowing therethrough can be selectively directed through one tower or the other. Commonly, such towers are oriented generally vertically when in use and are thus referred to as twin towers and are utilized at the site of a natural gas well for drying natural gas which exits the well.
One limitation associated with the aforedescribed twin towers relates to the capacity of the towers to effectively dry gas flowing therethrough. It is believed that in order to maximize the drying capacity of dryer desiccant, the dispersion or distribution of the gas flow across any cross section of desiccant must be relatively uniform. However, the desiccant held in a packed bed arrangement within each of the aforedescribed towers is known to channel or lift as the result of gas flow surges. Such channelling creates favored flow paths for gas moving from one end of the tower to another so that the distribution of the gas flow across each cross section of desiccant is not uniform. Thus, the packed bed arrangement of conventional twin tower dryers is believed to prevent the drying capacity of the dryer desiccant from being maximized.
Other limitations of the twin tower dryer relate to the relatively high pressure drop of gas flowing from one end of a tower to another and the difficulty attending the replacement of desiccant within each tower.
An object of the present invention is to provide a new and improved desiccant dryer which circumvents aforedescribed limitations associated with conventional twin tower dryers.
An additional object of the present invention is to provide such a dryer wherein the desiccant contained therein is prevented from channelling and provides a relatively uniform flow of gas across any cross section of desiccant contained therein.
Another object of the present invention is to provide such a dryer which requires no operating power thus rendering it practical for use in remote locations.
Still another object of the present invention is to provide such a dryer wherein the desiccant contained therein can be easily and quickly replaced.
Yet still another object of the present invention is to provide such a dryer which can be used in an assembly of dryers of like construction to permit a user to size the assembly to accommodate a wide variety of gas flow rates and flow pressure differentials as measured across the assembly.
A further object of this invention is to provide such a dryer providing a relatively low pressure drop in a gas line when placed therein.
A still further object of the present invention is to provide such a dryer which is efficient, effective and reliable in operation.
A yet still further object of the present invention is to provide such a dryer which is economical to construct.
One more object of the present invention is to provide such a dryer wherein the cost of desiccant for maintaining the dryer in operation is relatively low.